1. Field of the Invention
This invention relates to remote monitor systems for control bars having position indicating indicia thereon.
2. Description of the Prior Art
In the operation of refineries, chemical manufacturing facilities, storage facilities and so forth, it is occasionally necessary to penetrate the wall of a pipe or a pipeline for repair and maintenance purposes. In many instances such pipelines are under pressure, and frequently high pressure, or carry contents that are at a high temperature that would result in severe burns if contact is made with a workman, or in some instances the liquids within such pipelines are hazardous to health, such as ammonia or similar vapors and even more particularly, wherein liquids or gases flowing through the pipelines being tapped are explosive. Therefore tapping a pipeline can be hazardous. For this reason it is sometimes important that the operator of equipment, such as equipment for hot tapping a pipeline, be operated from a remote location so that in the event of a failure or accident, the operator will be safe from serious injury.
The essence of the invention herein described is a system that enables an operator to observe the position of a control bar that is typically part of pipeline plugging equipment by enabling the operator to read marking indicia on a plugging cylinder control bar. Further, the invention herein is concerned with a remote monitor system for a longitudinally positionable control bar that enables the operator to be constantly aware of the control bar's position but wherein the operator is remotely positioned to avoid the possibility of injury.
An example of the type of equipment for which the remote monitor system of this invention can be effectively employed is illustrated in pending U.S. patent application Ser. No. 11/132,773, filed May 19, 2005 entitled High Temperature Completion Plug, Charles D. Calkins and Jack E. Miller, Applicants.